HEAO 1 Observations of the Perseus cluster above 10 keV

Journal Article · Thu Jan 01 04:00:00 EST 1981 · Astrophys. J., Lett. Ed.; (United States)

DOI:https://doi.org/10.1086/183433· OSTI ID:6536099

Primini, F A; Basinska, E; Howe, S K; Land, F; Levine, A M; Lewin, W H.G.; Rothschild, R; Baity, W A; Gruber, D E; Knight, F K; Matteson, J L; Lea, S M; Reichert, G A

We present the results of HEAO 1 observations of the Perseus cluster from 10 to 150 keV in 1977 August and 1978 February and August. The spectrum exhibits a previously unknown hard (>25 keV) component in addition to the previously known thermal bremsstrahlung emission. The data presented show no significant evidence of variability from 10.5 keV to 93.5 keV, and a comparison of our results with earlier results indicates no strong evidence for variability above 25 keV over a time scale of approx. 4 yr. If the hard-component excess is due to NGC 1275, the data imply a 2--6 keV X-ray luminosity of approx.1 x 10/sup 44/ ergs s /sup -1/ for the galaxy, or approx.15% of the total cluster emission from 2 to 6 keV and a 25--40 luminosity of approx.8 x 10/sup 43/ ergs s/sup -1/. In the context of a model of hard-X-ray emission by inverse Compton scattering of relativistic electrons on the 2.7 K background, the X-ray spectrum, in conjuction with previously reported radio data, implies a magnetic field of B>10/sup -7/ gauss.

• Research Organization: Department of Physics and Center for Space Research, Massachusetts Institute of Technology
• OSTI ID: 6536099
• Journal Information: Astrophys. J., Lett. Ed.; (United States), Journal Name: Astrophys. J., Lett. Ed.; (United States) Vol. 243:1; ISSN AJLEA
• Country of Publication: United States
• Language: English

Related Subjects

640103* -- Astrophysics & Cosmology-- Quasi-Stellar
Radio
& X-Ray Sources-- (-1987)
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
BASIC INTERACTIONS
COMPTON EFFECT
COSMIC RAY SOURCES
COSMIC X-RAY SOURCES
ELASTIC SCATTERING
ELECTROMAGNETIC INTERACTIONS
ELECTROMAGNETIC RADIATION
EMISSION
GALAXIES
GALAXY CLUSTERS
HARD X RADIATION
INTERACTIONS
IONIZING RADIATIONS
MAGNETIC FIELDS
RADIATIONS
SCATTERING
SEYFERT GALAXIES
SPECTRA
X RADIATION
X-RAY GALAXIES
X-RAY SPECTRA